[Phys-l] correction: feeling gravity, or not

[John Denker <jsd@av8n.com>]

On 10/28/2006 10:57 AM, I wrote, alas:

>   We need not quantify the magnitude of the field;  by symmetry,
>   there exist "l/r" pairs, such that every "l" has an "r" of equal
>   magnitude.  So diagramming just the sign ("l" or "r") tells us
>   what we need to know.

Actually, to make my argument work as stated, we need to approximate
the magnitude of the field by a one-bit number, so that it is
piecewise uniform.  The right half of the field is uniform, and the
left half is uniform.

  Otherwise, you could divide the right half into a right-of-right
  quarter and a left-of-right quarter, and there would still be
  nonuniformities.  The argument depends on getting rid of the
  nonuniformities in each half.

  Sorry for any confusion this caused.

The punch line remains the same:

The only reason you feel gravity is because of nonuniformities
in the gravitational field.  Einstein's equivalence principle
asserts that a uniform field is unfeelable.